Soil density gauge and sampler



July 10, 1956 v. F. OBRCIAN sou DENSITY GAUGE AND SAMPLER Filed'Fe b. 4,1954 mvsmozg. Vlad/m1!" F Obrclan A TTO NEY United States Patent SOILDENSITY GAUGE AND SAMPLER Vladimir F. Obrcian, New York, N. Y.Application February 4, 1954, Serial No. 408,192

7 Claims. 01. 7s--42s.2

This invention relates to a device useful for determining soil densityand more particularly to a device capable of undisturbed sampling ofsoil for the purpose of determining the density thereof.

The principal object of the invention is the provision of a soilsampling device capable of removing a sample of soil and maintaining theoriginal density thereof during such removal. v

A still further object of the invention is the provision of a soilsampling device incorporating a measuring element whereby the soil isreceived directly by the measuring element.

A still further object of the invention is the provision of anundisturbed soil sampling and density measuring device of simple sturdyconstruction usable in the field in connection with various types ofsoils.

A still further object of the invention is .the provision of a soildensity sampler, the several portions of which may be used incooperative relationship in extracting a sample of soil and removing thesame from the sampling portion of the device.

I The .soil density gauge and sampler disclosed herein comprises animprovement in the art of undisturbed soil sampling and in the artrelating to determining the density of various soils. Those skilled inthe art will be familiar with the sand cone method wherein an excavationof predetermined size is made in the soil to be tested and theexcavation filled with sand, the weight of which is known to providecomparable factors useful in determining the density of the soil removedfrom the volume of the excavation.

Other methods, equally cumbersome in practice, include the methodwherein a rubber balloon is positionedin an excavation of predeterminedsize in the soil to be tested and the balloon filled with a liquid todetermine the exact volume which may then be compared with the weight ofthe removed soil to determine the density thereof. A third methodheretofore practiced comprises filling an excavation with oil andgetting the volume of excavation by means of the known weight of theoil. Paraflin wrapped specimens arealso used in a similar method.

All of'these methods are time consuming and relatively inaccurate inthat the density of the soil being tested must be determined by theforeign element introduced into theexcavation and by the known weightthereofas. comparedwith the volume used.

The present device permits the direct samplingof the soil through theuse of a hollow measuring element of predetermined capacity which isdriven, pushed or otherwise positioned in the soil to be tested fromwhence it is easily removed, the excess soil removed from the measuringelement and the soil in the sleeve weighed.

The density of the soil in pounds per cubic foot can be easilydetermined by dividing or multiplying the weight by an appropriatefactor. Thus, no foreign element is introduced into the procedure, aminimum of time is sulficient to take the sample and weight the same andno laborious careful excavation is necessary as in the past.

With the foregoing and other objects in view which will appear as thedescription proceeds, the invention resides in the combination andarrangement of parts and in the details of construction hereinafterdescribed and claimed, it being the intention to cover all changes andmodifications of the example of the invention herein chosen for purposesof the disclosure, which do not constitute departures from the spiritand scope of the invention.

The invention is illustrated in the accompanying drawing, wherein:

Figure 1 is a perspective view of the soil density gauge and sampler.

Figure 2 is a cross sectional view in enlarged detail of a portion ofthe soil density gauge and sampler shown in Figure 1.

Figure 3 is a schematic view of the soil density gauge and sampler inuse.

By referring to the drawing and Figure 1 in particular it will be seenthat the soil density gauge and sampler comprises a tripod frame, thelegs 10 of which are structural members formed for rigidity throughouttheir length. The outer ends of the legs 10 are outturned as at 11 toform feet which in turn are provided with downturned points 12-12.

Two of the legs 10 are permanently aflixed at their uppermost ends to acollar 14 while the third leg is removably afiixed thereto as byfasteners 15 to ease shipment. The collar 14 has a central opening 16therein which forms a vertically aligned guideway for a drive shaft 17which is positioned therethrough in a movable manner. The upper end ofthe drive shaft 17 is preferably threaded into a driving cap 18 andwhich cap 18 is provided with oppositely disposed facets 19 so that awrench can be applied thereto and the wrench rotated with respect to thedrive shaft 17. i

The lower end of the drive shaft 17 is frictionally secured in a socketmember 20 of inverted cup-like shape, as best shown inenlarged crosssectional detail in Figure 2 of the drawings. The socket member 20 has acentral opening 21 in its upper central area in which the lower end ofthe drive shaft 17 is received.- A set screw 22 is rotatably engaged ina transverse opening 23 in the socket member 20 so that an inner end ofthe set screw 22 directly engages the, drive shaft 17 and secures theparts in assembled relation. The lower annular skirt of the socketmember 20 is tapered as at 24 and provided with bayonet slots 25 and anannular shoulder 26 on its inner surface.

- By referring again to Figure l of the drawings it will be seen thatthe socket member 20 has a pair of oppositely disposed arms 2727extending outwardly therefrom. Each of the arms 27 is preferablythreaded into threaded openings 28 in the upper portion of the member20, as also shown in the cross sectional detail of Figure 2 of thedrawings. The openings 2828 also provide for the escape of air from thesocket member 20.

The outer ends of the arms 27 are provided with cross pieces 29-29 sothat they can be readily turned thereby and the arms 27 are providedtoprevent rotation ofthe member '20 and the drive shaft 17 with'respeetposed pins 3131 which engage the bayonet slots 25 and act to secure thesleeve 30 in position partially within the socket member and with itsupper annular edge in direct engagement with the shoulder 26 of thesocket member. The lower edge of the cutter cylinder 30 is 'annularlytapered to form an annular knife-like edge 32. Positioned within thesocket member 20 and the cutter cylinder 30 there is 'a spring presseddisc 33 and a coil spring 34 which is of a length normally comparablewith the total inner distance of the cutter cylinder 30 and socketmember 20 and compressible to a distance less than the length of thesocket member 20 and above the shoulder 26 therein.

The spring pressed disc 33 and coil spring 34 are loosely positioned inthe socket member 29 and cutter cylinder 30 when a soil sample is to betaken with the device. In taking such a sample, the device is positionedon the ground, the points 12 driven thereinto to secure the tripod-likeunit in stationary position, the spring pressed'disc 33 is positionedwithin the sleeve 30 and the same secured to the socket 20. The socket20 and cutter cylinder 30 are then moved downwardly into the soil to betested by striking the drive cap 18 with a suitable object until thecutter cylinder 30 is completely driven into the ground.

"It will occur to those skilled in the art that as this occurs, a sampleof the soil is separated from the soil of the area by the cuttercylinder 30 and the same rises within the cutter cylinder 30 against therelatively mild resistance of the spring pressed disc 33. The disc 33serves to maintain minimum pressure on the sample K being taken toprevent it from flying apart or becoming displaced and increasing itsvolume as might otherwise occur as a resultof the driving action of thecutter cylinder 30. If necessary, soil around the cutter cylinder 30 maybe and preferably is excavated, as in Figure 3, to facilitate thedriving action and thus assist in obtaining a better undisturbed soilsample.

At such time as the cutter cylinder 30 has penetrated "the soil asufficient depth, a trowel or other suitable article is slipped underthe bottom edge of the cutter cylinder 30 and the device twistedupwardly and away from the area to secure the sample within the cuttercylinder 30. The cutter cylinder 30 is then detached from the socketmember 20 and the soil extending beyond the ends of the cutter cylinder30 is removed and the remaining soil and cutter cylinder weighed therebydetermining the actual "weight of the known volume of the soil obtainedas a sample.

an the preferred form and size of the device, the cutter cylindercomprises a tubular member having a 2% innerdi'ameter and being 4 inlength. The sample 'of soil contained in the cutter cylinder 30 isweighed to determine its weight in grams and that weight divided by thenumeral 7 to yield the actual pounds per cubic foot of the soil andthereby determine its density. The density of the soil is obtained fromthe following equation:

where D is the inside diameter of the sleeve 30 and H is the height ofthe sleeve 30. Constant K can be thus chosen as an integer number suchas 7. Different numbers can be assigned to the constant K depending onthe diameter of the sleeve used; but a minimum ratio of H D equals 1 anda maximum ratio of H D equals 2 should be chosen because of the usualrequirements on the sample size during various soil testing procedures.

It will thus be seen that the soil density gauge and sampler disclosedherein may be conveniently and easily used to quickly and efficientlydetermine the soil density and meets the several objects of theinvention.

Having thus described my invention, what I claim is:

1. A soil sampler comprising a rigid frame including radially extendingcircumferentially spaced legs, a drive shaft positioned for verticalmovement in said frame, a socket secured to the lower end of said driveshaft and a cutter cylinder detachably secured to said socket.

2. The soil sampler set forth in claim 1 and further characterized bythe formation of said cutter cylinder with its projecting end tapered toa thin sharp annular edge.

3. The soil sampler set forth in claim 1 and further characterized byoppositely disposed arms removably positioned in said socket forengaging said legs to limit rotation of said socket.

4. The combination of the soil sampler set forth in claim 1 and a springand a soil retaining disc loosely positioned in said cutter cylinder andsocket, said spring and disc being movable inwardly completely out ofsaid cutter cylinder and completely into said socket.

5. The soil sampler set forth in claim 1 wherein said socket has aplurality of openings therein above said cutter cylinder and oppositelydisposed arms detachably positioned in said openings acting to limitrotation of said socket and cutter cylinder.

6. The soil sampler set forth in claim 1 wherein said legs compriseangularly positioned longitudinally trussed structures havinghorizontally disposed end portions, downturned prongs on said endportions inwardly from the ends thereof.

7. A soil sampler comprising a tripod frame of inverted semi-conicalconfiguration and including a central body having a vertical openingtherethrough, a drive shaft positioned through said vertical opening formovement with respect to said body member, a drive cap on the upper endof said drive shaft and a socket removably secured on the lower end ofsaid drive shaft, an open ended hollow measuring element positioned insaid socket and depending therefrom and forming with said socket achamber for the reception of soil, said socket having openings thereinand arms normally positioned in said openings and extending outwardlywith respect to said socket for registry with said tripodframe to limitrotation of said socket and measuring element, and resilient retractablemeans in said socket and measuring element for engaging a soil sample insaid measuring element and acting to maintain the original density ofthe said soil sample therein.

References Cited in the file of this patent UNITED STATES PATENTS146,901 Harrison Jan. 27, 1874 1,109,446 Melberg Sept. 1, 1914 2,301,478Tibbals et a1 'Nov. 10, 1942

